rr(k): fixed offset in building new route header

- related to the previous fix done to strict routing intermediary hop
(cherry picked from commit e154b2fb9f02d56d9c6a4b2d285791151ae0c8a3)
(cherry picked from commit 8db3e9c29b2cf1ff5c6f93411d3e9a90f7eb82ef)

modules_k/rr/loose.c

@@ -319,7 +319,7 @@ static inline int save_ruri(struct sip_msg* _m)
 	memcpy(s, RR_ROUTE_PREFIX, RR_ROUTE_PREFIX_LEN);
 	memcpy(s + RR_ROUTE_PREFIX_LEN, _m->first_line.u.request.uri.s,
 			_m->first_line.u.request.uri.len);
-	memcpy(s + ROUTE_PREFIX_LEN + _m->first_line.u.request.uri.len,
+	memcpy(s + RR_ROUTE_PREFIX_LEN + _m->first_line.u.request.uri.len,
 			ROUTE_SUFFIX, ROUTE_SUFFIX_LEN);
 
 	LM_DBG("New header: '%.*s'\n", len, ZSW(s));